Packet Data Network Voice Call Quality Monitoring

1. A method of controlling voice communication between calling and called telephone stations each connected through a respective switch to a public switched telephone network (PSTN) region and remotely located from each other, comprising the steps of: routing a voice call carrying two-way voice communication between said calling and called stations in digital packet format through a path of the Internet; changing the routing of said call between said calling and called stations from the Internet path to a circuit switched network path without terminating the call, thereby bypassing said packet data network while maintaining the voice communication call; and wherein said changing step is responsive to a signal input by one of said stations.

2. A method as recited in claim 1 , wherein said signal is input by a user.

3. A method as recited in claim 2 , wherein said signal is a DTMF signal.

4. A method as recited in claim 1 , wherein said signal is activated when a response time between said calling and called stations is greater than a predetermined threshold.

5. A method as recited in claim 4 , wherein said response time is determined by a traversal time of a test signal sent between said calling and called stations.

6. A communications system comprising: a public switched telecommunications network (PSTN) having a plurality of interconnected central office switching systems each connected to at least one subscriber line; a public data network separate from said switched telecommunications network comprising multiple remotely spaced routers for linking together paths of said public data network using transmission control protocols to provide connectionless packet service between remote locations of said public data network; at least two of said central office switching systems connected to a respective interface to said public data network, said central office switching systems providing selective connection between said interfaces and the subscriber lines connected to each of said central office switching systems; means for rerouting a voice call between subscriber lines of said two central office switching systems that traverse said public data network to a circuit switched network path in said PSTN in response to a predetermined condition, without terminating the existing voice call; and wherein said predetermined condition is receipt of a signal input from one of said subscriber lines.

7. A system as recited in claim 6 , wherein said signal is input by a user.

8. A system as recited in claim 7 , wherein said signal is a DTMF signal.

9. A system as recited in claim 6 , wherein said signal is activated when a response time between said central office switching systems is greater than a predetermined threshold.

10. A system as recited in claim 9 , wherein said response time is determined by a traversal time of a test signal sent between said central office switching systems.

11. A communications system comprising: a public switched telecommunications network (PSTN) having a plurality of interconnected central office switching systems each connected to at least one subscriber line; a public data network separate from said switched telecommunications network comprising multiple remotely spaced routers for linking together paths of said public data network using transmission control protocols to provide connectionless packet service between remote locations of said public data network; at least two of said central office switching systems connected to a respective interface to said public data network, said central office switching systems providing selective connection between said interfaces and the subscriber lines connected to each of said central office switching systems; and means for automatically rerouting a voice call between subscriber lines of said two central office switching systems that traverse said public data network to a non-packet data format voice path in said PSTN in response to a predetermined condition, without terminating the existing voice call; wherein said predetermined condition is the occurrence of an unacceptable level of quality of performance of said public data network, and each said interface comprises means for monitoring said data network during the course of transmission of said voice call through said public data network.

12. A communications network comprising: a switched telecommunications network having interconnected central office switching systems and having subscriber lines connected to said central office switching systems providing connection between terminals connected to said subscriber lines, each of said central office switching systems responding to a service request on a subscriber line connected thereto to selectively provide a communication connection between the requesting line and another selected subscriber line through the switched telecommunications network; a separate control network for said switched telecommunications network comprising a common channel interoffice signaling network including signal transfer points connected to said central office switching systems through signal switching points via links between said signal switching points and signal transfer points; a public data network separate from said switched telecommunications network comprising multiple remotely spaced routers for linking together paths of said public data network using transmission control protocols to provide connectionless packet service between remote locations of said public data network; at least two of said central office switching systems having connected thereto an interface to said public data network, said central office switching systems providing selective connection between said interfaces and the subscriber lines connected to each of said central office switching systems; each said interface comprising means for monitoring said public data network during the course of two-way voice communication of a voice call between a first and a second of said subscriber lines through said public data network to determine a quality of performance level in said public data network, and means for providing a signal to said control network indicating that said performance level is unacceptable; and wherein said public data network is the Internet and said control network is responsive to said signal to reroute said voice call through said switched telecommunications network to bypass the Internet while maintaining the two-way voice communication call.

13. A communication network as recited in claim 12 , wherein said central office switching systems comprise means responsive to said control network for bridging said first and second subscriber lines to the rerouted switched telecommunications path.

14. A method of controlling voice communication between calling and called telephone stations each connected through a respective switch to a public switched telephone network (PSTN) region and remotely located from each other, comprising the steps of: routing a voice call carrying two-way voice communication between said calling and called stations in digital packet format through a path of the Internet; and changing the routing of said call between said calling and called stations from the Internet path to a non-packet data format voice telephone network voice path without terminating the call, thereby bypassing said packet data network while maintaining the voice communication call; wherein said changing step comprises: monitoring said packet data network during the course of transmission of said voice call through said packet data network path to determine a quality of performance level; comparing the performance level determined in said monitoring step with a predetermined threshold level; and rerouting the call to said voice telephone network voice path if the performance level of said packet data network as monitored in said monitoring step is below said predetermined threshold.